Tim Peake and space station crew mates return to Earth

As skywatchers and scientists converge on a transcontinental band of totality for Monday’s solar eclipse in the United States, engineers in Europe are building a unique pair of satellites to create artificial eclipses lasting for hours — a feat that that could be a boon for solar physicists but will escape the view of Earth-bound spectators.

Europe’s LISA Pathfinder mission — a fundamental physics lab launched last year to a point a million miles from Earth — has demonstrated the mind-boggling technology required for a future space-based observatory to listen for faint, low-frequency vibrations emitted by invisible objects in the most distant pockets of the universe, scientists said this week.

Research just published in Nature describes two bright, extremely high-altitude plumes observed on Mars by amateur astronomers in March and April 2012, but attempts at explaining the phenomena defy our current understanding of the Martian upper atmosphere.